Received: 29 April 2020
Accepted: 18 March 2021
First Online: 31 March 2021
: Recruitment of dairy cows into this work was done in consultation with the veterinarians, and sampling was performed after the permission of the dairy farms` owners in written consent. Every individual was provided with a document explaining the purpose and method of sample collection. The study was approved by the committee of Animal Welfare and Research Ethics, Faculty of Veterinary Medicine, Zagazig University, Egypt.
: Not applicable.
: The authors declare that they have no competing interests.